Underwater breathing regulator



FIG. 1 is a top plan view of an underwater breathing regulator embodying my new design;

FIG. 2 is a side elevation of the device of FIG. 1 as seen from the bottom of FIG. 1;

FIG. 3 is a bottom plan view of the device of FIG. 1;

FIG. 4 is an end view of the device of FIG. 1 taken from the right-hand side as shown in FIG. 1;

FIG. 5 is a side elevation of the side of the device _opposite the side shown in FIG. 2; and

FIG. 6 is an end view of the device of FIG. 1 as seen from the left-hand side of FIG. 1. 

The ornamental design for an underwater breathing regulator, as shown and described. 